Experience

Experience Points (XP) are an abstract measure of the experience, knowledge, "life-force", and training that a PC gains while adventuring. They are gained from RPBonus, beating monsters, sometimes from DM events, or completing rare quests.

The scripting formula used for monster XP awards is quite complicated and its exact definition on Arelith is not a public knowledge. Some factors taken into consideration include:

Challenge rating of monster (Party)
Level of highest character within sight of a creature (Party)
Number of characters within sight of a creature (Party)
Number and level of summoned familiars, summons, animal companions and other friendly monsters within sight of killed monster (Party)
Level of your character (Personal/party if you have the highest level of the party)
Effective character level (ECL) (Personal)
~~Multiclassing penalty~~ Multiclass Penalty has been removed from Arelith.

The notes tagged with (Personal) do not affect other characters, while (party) indicates that these affect the experience reward of all characters in line of sight.

Whereas normally being in a party splits the experience gain, Arelith reverses this mechanic. For each member in your party up to 5, the experience received will increase. From 6 and more, the experience will decline negatively.

"Friendly monsters" can be many things. Any non-hostile NPC, even dead NPC with lingering bodies and "live statues" may affect the calculation negatively. One notable exception to this are Lassoed creatures, which don't affect experience in any way.

ECL doesn't reduce or increase the experience gain from RPBonus bonus.

Explained the other way around:

When it comes to experience, it works something like this:

CR of the monster,

Which is then averaged to the character with the highest level in line of sight,

that is then increased/decreased based on the number of characters in the party,

To be finally averaged a last time by your character's level, and multiplied (positively or negatively) by your ECL.

The first two factors are the most important, as they define your base experience gain.

External links

Experience point on NWNWiki